FIG. 1 shows the configuration described in Patent Literature 1 as a conventional example of such a connector-equipped plug. In FIG. 1, reference numeral 11 denotes a main body portion and 12 denotes an optical connector which is built into the main body portion 11. The optical connector 12 has a latch portion 12a for being latched to a mating optical module to be connected thereto. Reference numeral 13 denotes a coupling member to be coupled to a mating adaptor storing the optical module.